This invention relates to hand-held cutting tools, and more specifically to cutting tools for applying relatively large forces in a highly controlled manner to the object to be cut.
In many applications of leather and glass cutting, such as in the construction of stained glass works and artistic works in leather, a relatively high amount of pressure must be applied to the leather or glass while scoring or cutting, yet the scoring or cutting must be simultaneously performed in a highly controlled and delicate manner. For example, in the creation of various stained glass works, it is often necessary to make numerous curved scores which require that the scoring be done by hand in a very controlled and precise manner. Additionally, in many instances when segments of glass must be cut out of glass panes it is necessary that very large forces be applied by the hand very precisely so that the segment is easily removed without cracking or breaking the surrounding glass.
The conventional hand-held glass cutter comprises generally a shaft having a carbide cutting wheel on one end and a forefinger depression located near the cutting wheel. The conventional glass cutter is difficult to grip and allows forces to be applied by the hand only at one point, namely at the forefinger depression. Accordingly, during long cuts the hand becomes fatigued and the depth of cut correspondingly decreases toward the end of the cut, thereby preventing completion of the cut and often resulting in the breaking of the surrounding glass. Additionally, because of the inability to properly grip the conventional cutter, it is difficult to perform delicate cutting maneuvers on the glass. These instruments were designed previously to the development of high pressure cutting techniques and are not suitable for use when such techniques are employed.
A removable holder adapted for the conventional glass cutter, as disclosed in U.S. Pat. No. 2,892,291, permits both the middle finger and the thumb to grip the cutter. The holder disclosed in the U.S. Pat. No. 2,892,291, when fitted onto a conventional glass cutter, makes the performance of curved cuts difficult because gripping the holder requires that the middle finger and thumb be squeezed together. It is thus difficult to apply side forces in order to turn the cutting wheel into a curved path and, in addition, because of the constant squeezing of the middle finger and thumb to grip the cutter, the hand becomes easily fatigued.